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Engaget's SpaceX gets FCC approval to deploy thousands more internet satellites says

SpaceX's plan to build a global, high-speed wireless internet network using satellites has taken another step forward. The FCC approved the company's request to deploy more than 7,000 very-low-Earth orbit satellites for its Starlink network. It follows the regulator giving SpaceX the green light in March to launch 4,425 satellites.

When it's complete, Starlink will be comprised of almost 12,000 satellites that will blanket the planet with a persistent internet connection. That should mean people in rural areas or other locations where more traditional types of connections are impractical can access a network with promised speeds of up to 1 Gbps.

The article links to a November 15, 2018 FCC release FCC Boosts Satellite Broadband Connectivity and Competition in the United States. Which mentions approvals for several space companies and constellations.

In a Memorandum Opinion, Order and Authorization, the Commission granted SpaceX’s application with certain conditions, authorizing SpaceX to construct, deploy, and operate a new very-low-Earth orbit constellation of more than 7,000 satellites using V-band frequencies. The Commission also granted SpaceX’s request to add the 37.5-42.0 GHz, and 47.2-50.2 GHz frequency bands to its previously authorized NGSO constellation. The Commission’s action provides SpaceX with additional flexibility to provide both diverse geographic coverage and the capacity to support a wide range of broadband and communications services for residential, commercial, institutional, governmental, and professional users in the United States and globally.


Question: So I'd like to ask how low is VLEO? SpaceX's very-low-Earth orbit constellation of more than 7,000 satellites?

I haven't heard the orbit called VLEO yet, but it mush be a lot lower than the orbits of the original 4,425 approved, which are in the 1,100 to 1,300 km ballpark. See SpaceX's 4,425 satellite constellation - what's the method to the madness? for details.

SpaceX first 4,425 satellites

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  • $\begingroup$ Also SpaceX revised the orbit for Starlink, down from 1100-1300 to 525Km I believe. $\endgroup$ – geoffc Nov 16 '18 at 17:00
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Per Space News, reviewing the applications, VLEO in this context is below 350 km orbit.

Of the four, SpaceX is by far the largest with 7,518 satellites constituting what it calls a “very low Earth orbit,” or VLEO constellation that would operate slightly below 350-kilometers.

What is interesting to me is the comment that follows:

At that altitude, SpaceX says atmospheric drag would pull spent satellites down in one month, assuaging concerns about the magnitude of debris that that many satellites could create in higher orbits.

I read that, in a similar comment they made about the main 525Km orbit Starlink plan, that it would reenter in 6 months. Which is to say, unpowered, out of control, it would re-enter in 1-6 months. As opposed to the lifetime of such a satellite would be 1-6 months (for the two cases).

I.e. Once the vehicle is out of fuel to maintain orbit, THEN it has the shortened lifespan.

As you can imagine, a constellation with 7000 satellites that last a total of one month each is impossible or at best improbable.

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    $\begingroup$ How much would it need to stay in orbit longer than a month? If takes an ounce of fuel to keep a 1 pound satellite in orbit 2 years at 350KM, it might be practical. $\endgroup$ – James Jenkins Nov 16 '18 at 17:10
  • $\begingroup$ An excellent second question. $\endgroup$ – geoffc Nov 16 '18 at 17:37
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    $\begingroup$ Always in another question. :) as a hint I believe they plan to use Hall effect electric thrusters, so fuel masses may be low enough. $\endgroup$ – geoffc Nov 16 '18 at 17:46
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    $\begingroup$ New related How much fuel to maintain VLEO for communication satelites? $\endgroup$ – James Jenkins Nov 16 '18 at 17:59

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